1. Field of the Invention
The present invention relates to electromagnetic radiation systems for medical or cosmetic applications, and more particularly to devices providing one or more laser radiation wavelengths for medical or cosmetic applications.
2. Invention Disclosure Statement
Laser devices have shown many advantages in comparison with other technologies for medical and cosmetic applications where light of the required spatial or temporal coherence could not be produced using simpler technologies. However, the technology has sometimes lead to expensive, heavy, bulky and complicated devices, especially when high energy or power density is required for a given medical application.
Furthermore, these laser devices can usually give only a single laser wavelength at a time when in some circumstances it would be desirable to have a more powerful laser device capable of providing more than one laser wavelength, as this offers an broader range of therapeutic effects.
Dimensionally, fiber lasers usually have sizes comparable to less than a single strand of hair. For single mode fibers, typically, the core diameter is about 8-10 microns, with an overall cladding diameter of 125 microns and then various types of jacketing material are applied for added mechanical strength protection, typically with outer diameters of 500 microns, to over a few microns for metal over-jacketed fibers.
To overcome the disadvantages of prior art laser devices for medical or cosmetic treatments, a fiber laser device for medical/cosmetic procedures by use of a tunable fiber laser is disclosed in U.S. Pat. No. 6,723,090 by Altshuler et al. The fiber laser is included in a box containing control and other electronics, a cooling mechanism, a diode laser, suitable optics and an acoustic module for tuning the wavelength of the fiber laser. Part of the fiber laser is in the box and extends through an umbilical up to a handpiece. Extreme caution has to be taken as the main component of the system, namely the fiber laser is only covered by an umbilical. Furthermore, the high power that can be achieved is limited as the length of the fiber laser is restricted to the length of the umbilical. Alternatively, all these components can be inside a handpiece, leading to a heavy and clumsy system whose weight is increased when a longer fiber laser length is desired for high energy applications.
Another example of medical laser apparatus comprising fiber lasers is disclosed in U.S. Pat. No. 7,408,963 by Hayashi at al. The medical apparatus provides visible laser beams each having a different wavelength, having an inexpensive structure. However, this medical apparatus has a limited versatility, as many prior art medical laser devices have, as its application is limited to the use of a single laser wavelength at a time and hence a limited therapeutic effect is achieved. Whereas it would be desirable to have a laser device whose laser wavelength output could be adjusted to obtain a combined therapeutic effect, controlling the degree of vaporization, coagulation and ablation, without the need to choose only a single effect. Furthermore, the invention disclosed herein is also suitable for high power applications, but the invention of Hayashi at is for applications which do not need to cope with high intensity. It is an inexpensive structure however its application is limited to the use of a lower power, single laser wavelength and hence the versatility of the system is diminished.
Thus, there is a need for a versatile, compact and lightweight laser system for medical and cosmetic applications, involving the delivery of laser energy to the tissue in an efficient manner and providing the desired therapeutic effect, wherein multiple wavelengths and high powers are desirable. Present invention addresses these needs by providing economic, versatile, safe and efficient laser systems.